Fault positioning method for filtering impedance of wire connector

Abstract

The invention provides a fault positioning method for filtering impedance of a wire joint, which comprises the following steps of: recording fault recording data after protection action so as to carry out fault type judgment, and carrying out fault impedance calculation by adopting a symmetric fault analysis method according to the fault type; determining the number of lines, and setting a positive sequence impedance value, a negative sequence impedance value and a zero sequence impedance value of each section of line in unit length, and a connector lug positive sequence impedance compensation value of each section of line; determining a fault position by combining the calculated average value of the plurality of fault impedances; and outputting whether the fault position, the fault type, the fault line segment interval and the fault distance measurement are in the whole line range or not. According to the fault positioning method for filtering the impedance of the wire connector, single-end power supply fault positioning and double-end power supply fault positioning are realized by using a fault analysis impedance method, the fault position can be accurately positioned, manpower and material resources are saved, a fault line segment interval can be output, whether fault distance measurement is in a whole line range or not can be judged, and the fault positioning accuracy is improved. And the positioning accuracy is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of fault location, and in particular to a fault location method for filtering out wire joint impedance. Background Art

[0002] The use of electric energy is inseparable from transmission lines. When a transmission line fails, without fault recording and protection distance measurement information, manual search is the only option. However, manual search for the fault point is time-consuming and labor-intensive, and the results are ineffective. Furthermore, with the increasing complexity of power grid structures, the annual increase in electricity load, and the large-scale integration of new energy sources, the requirements for efficient handling of voltage-level faults are increasing. Furthermore, the power network spans long distances, the actual working environment is complex, users' experience with electricity is constantly improving, and the business environment has also set higher standards for power supply reliability. Therefore, the traditional manual inspection method of finding voltage-level lines is difficult to accurately locate the fault location when locating transmission line faults, and no longer meets the requirements. Summary of the Invention

[0003] The present invention aims to at least solve the technical problems existing in the prior art, and in particular innovatively proposes a fault location method for filtering out the impedance of a wire joint.

[0004] In order to achieve the above-mentioned object of the present invention, the present invention provides a fault location method for filtering out the impedance of a wire joint, the method comprising:

[0005] S1. Record the fault waveform data after the protection action;

[0006] S2. Determine the fault type according to the fault recording data; wherein the fault types include single-phase grounding, three-phase short circuit, inter-phase grounding short circuit, and inter-phase non-grounding short circuit;

[0007] S3. Calculate the fault impedance using a symmetrical fault analysis method according to the fault type.

[0008] S4. Determine the number of lines, and set the positive sequence impedance value, negative sequence impedance value, zero sequence impedance value per unit length of each line segment, and the positive sequence impedance compensation value of the terminal of each line segment;

[0009] S5. Calculate an average value of the plurality of fault impedances, and calculate the fault distance based on the average value, the negative-sequence impedance value, the zero-sequence impedance value, and the positive-sequence impedance compensation value of the connection head of each section of the line to determine the fault location;

[0010] S6. Output the fault location, fault type, fault line segment interval, and whether the fault distance is within the entire line range.

[0011] Furthermore, step S1 specifically includes:

[0012] S101. When the input information TRIGG_XCOF is TRUE, determine the value of the positioning selection mode;

[0013] S102: When the positioning selection mode is 1, it is a single-ended power supply, and the voltage U at one end is recorded. A 、U B 、U C , current I A , I B , I C Sampling value, single-ended power supply fault ranging and identification;

[0014] S103. Calculate the effective value of voltage and current and the real and imaginary parts of each data using the data.

[0015] Furthermore, the step S2 specifically includes:

[0016] S201, calculating the fault components of phase A, phase B, and phase C according to the fault recording data;

[0017] S202: Determine the fault type based on the current and voltage of phase A, phase B, and phase C.

[0018] Furthermore, in step S201, the calculation formula is:

[0019] A phase current power frequency variation:

[0020] Phase B current power frequency variation: Phase C current power frequency variation: in, The A-phase current vector value of the k-sampling point in the current fault cycle; Represents the A-phase current vector value at k sampling points one cycle before the fault;

[0021] Represents the A-phase current vector value at k sampling points 2 cycles before the fault;

[0022] The B-phase current vector value of the k-sampling point in the current fault cycle;

[0023] Represents the B-phase current vector value at k sampling points one cycle before the fault;

[0024] represents the B-phase current vector value at k sampling points 2 cycles before the fault;

[0025] Represents the C-phase current vector value at the k sampling point of the current fault cycle;

[0026] Represents the C-phase current vector value at k sampling points one cycle before the fault;

[0027] The C-phase current vector value at the k sampling point 2 cycles before the fault is calculated using the local measurement value:

[0028]

[0029] Current sequence component calculation: Zero sequence: Positive sequence: Negative sequence: Voltage sequence component calculation: Zero sequence:

[0030] Positive sequence:

[0031] Negative sequence:

[0032] Superposition current:

[0033] Phase A current:

[0034] Phase B current:

[0035] Phase C current:

[0036] Superimposed voltage:

[0037] Phase A voltage:

[0038] Phase B voltage:

[0039] Phase C voltage:

[0040] Furthermore, in step S202, the fault type is determined as follows:

[0041] When 0≤|I1-I2|≤0.2*I n And 0≤|I0-I1|≤0.2*I n N0≤|I0-I2|≤0.2*I n and and and and When the fault type is determined to be single-phase grounding of phase A;

[0042] When 0≤|I1-I2|≤0.2*I n And 0≤|I0-I1|≤0.2*In N0≤|I0-I2|≤0.2*I n and and and and When the fault type is determined to be single-phase grounding of phase B;

[0043] When 0≤|I1-I2|≤0.2*I n And 0≤|I0-I1|≤0.2*I n and 0≤|I0-I2|≤0.2*I n and and and and When the fault type is determined to be single-phase grounding of phase C;

[0044] When 0≤|I1-I2|≤0.2*I n and and and When the fault type is determined to be a short circuit between phases AB without grounding;

[0045] when and and and When , the fault type is determined to be BC phase-to-phase short circuit;

[0046] When 0≤|I1-I2|≤0.2*I n and and and When , the fault type is determined to be CA phase-to-phase short circuit;

[0047] When 0.2*I n <|I1-I2| and and and When , the fault type is determined to be a ground short circuit between phases AB;

[0048] When 0.2*I n <|I1-I2|

[0049] and and and When , the fault type is determined to be a ground short circuit between phases BC;

[0050] When 1.5*IN<|I1-I0| and 1.5*IN<|I1-I2|

[0051] and and and When , it is determined that the fault type is three-phase short circuit;

[0052] Where I1 represents the effective amplitude of the positive sequence current in the current fault cycle;

[0053] I2 represents the effective amplitude of the negative sequence current in the current fault cycle;

[0054] I0 represents the effective amplitude of the zero-sequence current in the current fault cycle;

[0055] Indicates the AB phase fault component line current vector value of the current fault cycle;

[0056] Indicates the BC phase fault component line current vector value of the current fault cycle;

[0057] Represents the line current vector value of the CA phase fault component in the current fault cycle;

[0058] I n Indicates the secondary rated current value of the current transformer CT.

[0059] Furthermore, the step S3 specifically includes:

[0060] S301. Construct a single-phase ground fault network and derive the following equivalent equation:

[0061]

[0062] Since it is single-phase grounding, there are: Taking negative sequence current as the standard, the simplified formula is:

[0063]

[0064] By taking the imaginary part to eliminate the influence of transition resistance, the fault impedance is calculated as:

[0065]

[0066] When the fault type is determined, the phase voltage and negative sequence current of the corresponding phase are input to calculate the fault impedance;

[0067] S302. Construct a phase-to-phase short-circuit ungrounded fault network and derive the following equivalent equation:

[0068]

[0069] Because there are: and Taking negative sequence current as the standard, the simplified formula is:

[0070]

[0071] The imaginary part is taken to eliminate the influence of transition resistance, and the fault impedance is calculated as:

[0072]

[0073] When the fault type is determined, the sequence voltage and sequence current of the corresponding phase are brought in to obtain the fault impedance;

[0074] S303. Construct a phase-to-phase short-circuit grounding fault network and derive the following simplified equivalent formula:

[0075]

[0076] The imaginary part is taken to eliminate the influence of transition resistance, and the fault impedance is calculated as:

[0077]

[0078] When the fault type is determined, the sequence voltage and sequence current of the corresponding phase are brought in to obtain the fault impedance;

[0079] S304. Construct a phase-to-phase short-circuit grounding fault network and derive the following simplified equivalent equation:

[0080]

[0081] By taking the imaginary part to eliminate the influence of transition resistance, the fault impedance is calculated as:

[0082]

[0083] When the fault type is determined, the sequence voltage and sequence current of the corresponding phase are input to obtain the fault impedance.

[0084] Furthermore, in step S4,

[0085] The positive sequence impedance value is denoted as χ n1 (n represents the segment number, n = 1, 2, 3..., 10);

[0086] The negative sequence impedance value is equal to the positive sequence impedance value;

[0087] The zero-sequence impedance value is recorded as χ n0 ;

[0088] The positive sequence impedance compensation value of each line segment is recorded as χ np .

[0089] Furthermore, in step S5, calculating the average value of the plurality of fault impedances specifically includes:

[0090] At least three times of fault impedance data are used to calculate the average value X012 total_平均值, X1 total_平均值 , and convert it into a primary value, specific conversion unit:

[0091]

[0092] Furthermore, in step S5, calculating the fault distance specifically includes:

[0093] S501. For a single-phase grounding fault, the distance determination method for each fault point on the entire line is as follows:

[0094] 1) Determine the number of lines to be 10 sections;

[0095] When X012 total__平均值_1 ≤2*(X 1p +X 1p +3*X 1p )+2*χ 11 *L1+χ 10 *L1, indicating that the fault is within line L1; the specific distance measurement is:

[0096] Indicates that the requirements are met. If L is calculated 故障位置 >L1 means the distance measurement exceeds the limit;

[0097] 2) When

[0098] 2*(X 1p +X 1p +3*X 1p )+2*χ 11 *L1+χ 10 *L1 <X012 total_平均值_1 ≤2*(X 1p +X 1p +3*X 1p )+2*χ 11 *L1+χ 10 *L1+2*(X 2p +X 2p +3*X 2p )+2*χ 21 *L2+χ 20 *L2, indicating that the fault is within line L2; the specific distance measurement is:

[0099]

[0100] Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2 means the distance measurement exceeds the limit;

[0101] 3) When

[0102] 2*(X 1p +X1p +3*X 1p )+2*χ 11 *L1+χ 10 *L1+2*(X 2p +X 2p +3*X 2p )+2*χ 21 *L2+χ 20 *L2 <X012 total_平均值_1 ≤2*(X 1p +X 1p +3*X 1p )+2*χ 11 *L1+χ 10 *L1+2*(X 2p +X 2p +3*X 2p )+2*χ 21 *L2+χ 20 *L2+2*(X 3p +X 3p +3*X 3p )+2*χ 31 *L3+χ 30 *L3, indicating that the fault is within line L3; the specific distance measurement is:

[0103]

[0104] , indicating that the requirements are met, if L is calculated 故障位置 >L1+L2+L3 means the distance measurement exceeds the limit;

[0105] 4) When

[0106] 10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3 <X012 total_平均值_1 ≤10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ41 *L4+χ 40 *L4

[0107] When , it means the fault is in line L4; the specific distance measurement is:

[0108] Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4 means the ranging is out of limit;

[0109] 5) When

[0110] 10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4 <X012 total_平均值_1 ≤10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4+10*X 5p +2*χ 51 *L5+χ 50 *L5

[0111] When , it means the fault is within line L5; the specific distance measurement is:

[0112] Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4+L5 means the ranging is out of limit;

[0113] 6) When

[0114] 10*X 1p +2*χ 11 *L1+χ 10*L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4+10*X 5p +2*χ 51 *L5+χ 50 *L5 <X012 total_平均值_1 ≤10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4+10*X 5p +2*χ 51 *L5+χ 50 *L5+10*X 6p +2*χ 61 *L6+χ 60 *L6

[0115] When , it means the fault is in line L6; the specific distance measurement is:

[0116] Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4+L5+L6 means the ranging is out of limit;

[0117] 7) When

[0118] 10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40*L4+10*X 5p +2*χ 51 *L5+χ 50 *L5+10*X 6p +2*χ 61 *L6+χ 60 *L6 <X012 total_平均值_1 ≤10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4+10*X 5p +2*χ 51 *L5+χ 50 *L5+10*X 6p +2*χ 61 *L6+χ 60 *L6+10*X 7p +2*χ 71 *L7+χ 70 *L7

[0119] When , it means the fault is in line L7; the specific distance measurement is:

[0120] Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4+L5+L6+L7 indicates that the ranging is out of limit;

[0121] 8) When

[0122] 10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4+10*X 5p +2*χ 51 *L5+χ50 *L5+10*X 6p +2*χ 61 *L6+χ 60 *L6+10*X 7p +2*χ 71 *L7+χ 70 *L7 <X012 total_平均值_1 ≤10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4+10*X 5p +2*χ 51 *L5+χ 50 *L5+10*X 6p +2*χ 61 *L6+χ 6O *L6+10*X 7p +2*χ 71 *L7+χ 70 *L7+10*X 8p +2*χ 81 *L8+χ 80 *L8

[0123] When , it means the fault is in line L8; the specific distance measurement is:

[0124] Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4+L5+L6+L7+L8 indicates that the ranging is out of limit;

[0125] 9) When

[0126] 10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41*L4+χ 40 *L4+10*X 5p +2*χ 51 *L5+χ 50 *L5+10*X 6p +2*χ 61 *L6+χ 60 *L6+10*X 7p +2*χ 71 *L7+χ 70 *L7+10*X 8p +2*χ 81 *L8+χ 80 *L8 <X012 total_平均值_1 ≤10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4+10*X 5p +2*χ 51 *L5+χ 50 *L5+10*X 6p +2*χ 61 *L6+χ 60 *L6+10*X 7p +2*χ 71 *L7+χ 70 *L7+10*X 8p +2*χ 81 *L8+χ 80 *L8+10*X g9 +2*χ91*L9+χ 90 *L9 indicates that the fault is within line L9; the specific distance measurement is:

[0127] Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4+L5+L6+L7+L8+L9 indicates that the ranging is out of limit;

[0128] 10) When

[0129] 10*X 1p +2*χ 11 *L1+χ 10*L1+10*X 2p +2*x 21 *L2+x 20 *L2+10*X 3p +2*x 31 *L3+x 30 *L3+10*X 4p +2*x 41 *L4+x 40 *L4+10*X 5p +2*x 51 *L5+x 50 *L5+10*X 6p +2*x 61 *L6+x 60 *L6+10*X 7p +2*x 71 *L7+x 70 *L7+10*X 8p +2*x 81 *L8+x 80 *L8+10*X 9p +2*x 91 *L9+x 90 *L9 <X012 total_平均值_1 ≤10*X 1p +2*x 11 *L1+x 10 *L1+10*X 2p +2*x 21 *L2+x 20 *L2+10*X 3p +2*x 31 *L3+x 30 *L3+10*X 4p +2*x 41 *L4+x 40 *L4+10*X 5p +2*x 51 *L5+x 50 *L5+10*X 6p +2*x 61 *L6+x 60 *L6+10*X 7p +2*x 71 *L7+x 70 *L7+10*X 8p +2*x 81 *L8+x 80 *L8+10*X 9p +2*x 91 *L9+x 90 *L9+10*X 10p +2*x101 *L 10 +χ 100 *L 10

[0130] When , it means the fault is within line L10; the specific distance measurement is:

[0131] Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4+L5+L6+L7+L8+L9+L 10 Indicates that the distance measurement exceeds the limit;

[0132] S502. For phase-to-phase grounding faults, phase-to-phase ungrounded faults, and three-phase short-circuit faults, the distance determination method for each fault point on the entire line is as follows:

[0133] 1) When X1 tota_平均值_1 ≤2*X 1p +χ 11 *L1, indicating that the fault is within line L1; the specific distance measurement is:

[0134] Indicates that the requirements are met. If L is calculated 故障位置 >L1 means the distance measurement exceeds the limit;

[0135] 2) When 2*X 1p +χ 11 *L 11 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2, indicating that the fault is within line L2; the specific distance measurement is:

[0136] Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2 means the distance measurement exceeds the limit;

[0137] 3) When

[0138] 2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ31 *L3

[0139] When , it means the fault is in line L3; the specific distance measurement is:

[0140] Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3 means the distance measurement exceeds the limit;

[0141] 4) When

[0142] 2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4

[0143] When , it means the fault is in line L4; the specific distance measurement is:

[0144]

[0145] Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4 means the ranging is out of limit;

[0146] 5) When

[0147] 2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p+χ 41 *L4+2*X 5p +χ 51 *L5 indicates that the fault is within line L5; the specific distance measurement is:

[0148] Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4+L5 means the ranging is out of limit;

[0149] 6) When

[0150] 2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p +χ 61 *L6, indicating that the fault is within line L6; the specific distance measurement is:

[0151] Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4+L5+L6 means the ranging is out of limit;

[0152] 7) When

[0153] 2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ51 *L5+2*X 6p +χ 61 *L6 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p +χ 61 *L6+2*X 7p +χ 71 *L7

[0154] When , it means the fault is in line L7; the specific distance measurement is:

[0155] Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4+L5+L6+L7 indicates that the ranging is out of limit;

[0156] 8) When

[0157] 2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p +χ 61 *L6+2*X 7p +χ 71 *L7 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p+χ 61 *L6+2*X 7p +χ 71 *L7+2*X 8p +χ 81 *L8

[0158] When , it means the fault is in line L8; the specific distance measurement is:

[0159] Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4+L5+L6+L7+L8 indicates that the ranging is out of limit;

[0160] 9) When

[0161] 2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p +χ 61 *L6+2*X 7p +χ 71 *L7+2*X 8p +χ 81 *L8 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p +χ 61 *L6+2*X 7p +χ 71 *L7+2*X 8p +χ 81 *L8+2*X 9p +χ 91 *L9

[0162] When , it means the fault is in line L9; the specific distance measurement is:

[0163] Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4+L5+L6+L7+L8+L9 indicates that the ranging is out of limit;

[0164] 10) When

[0165] 2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p +χ 61 *L6+2*X 7p +χ 71 *L7+2*X 8p +χ 81 *L8+2*X 9p +χ 91 *L9 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p +χ 61 *L6+2*X 7p +χ 71 *L7+2*X 8p +χ 81 *L8+2*X 9p +χ 91 *L9+2*X 10p +χ 101 *L 10 When , it means the fault is within line L10; the specific distance measurement is:

[0166] Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4+L5+L6+L7+L8+L9+L 10 Indicates that the distance measurement exceeds the limit.

[0167] The beneficial effects of the present invention are that the fault type is identified through fault recording data, and then the fault impedance is calculated by using a symmetrical fault analysis method according to the fault type, the positive-sequence impedance value, negative-sequence impedance value, and zero-sequence impedance value per unit length of each line section, as well as the positive-sequence impedance compensation value of the terminal of each line section, are set, and the fault distance is calculated in combination with the average value of multiple fault impedances to determine the fault location; the fault analysis impedance method is used to realize single-end power supply fault location and double-end power supply fault location, which can accurately locate the fault location and save manpower and material resources. At the same time, the fault line segment interval and whether the fault distance is within the entire line range can be output, thereby improving the positioning accuracy.

[0168] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0169] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which:

[0170] Figure 1 It is a flow chart of the fault location method for filtering out wire joint impedance according to the present invention.

[0171] Figure 2 This is a schematic diagram of a single-phase grounding fault network in the present invention.

[0172] Figure 3 This is a schematic diagram of a phase-to-phase short-circuit ungrounded fault network in the present invention.

[0173] Figure 4 This is the first schematic diagram of the phase-to-phase short-circuit grounding fault network in the present invention.

[0174] Figure 5 This is the second schematic diagram of the phase-to-phase short-circuit grounding fault network in the present invention. DETAILED DESCRIPTION

[0175] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0176] The present invention is based on a fault location SCEFRFLO function module, which utilizes a fault analysis impedance method to implement single-ended power supply fault location and double-ended power supply fault location.

[0177] Among them, the locking function BLOCK can be controlled through the switch input of the relay program, horizontal communication input, internal signal control input or GOOSE information input.

[0178] BLOCK means blocking the entire phase-to-phase distance protection module, realizing global blocking mode. In the "Block All" mode, that is, BLOCK is TRUE, all functions will be blocked and the corresponding timers and registers will be reset.

[0179] TRIGG_XCOF indicates that the distance measurement operation of this module is started. That is, TRIGG_XCOF is TRUE, the module starts the distance measurement operation, records the fault distance, and records the current and voltage at both ends.

[0180] like Figure 1 As shown, the present invention provides a fault location method for filtering out wire joint impedance, comprising:

[0181] S1. Record the fault waveform data after the protection action;

[0182] Step S1 specifically includes:

[0183] S101. When the input information TRIGG_XCOF is TRUE, determine the value of the positioning selection mode;

[0184] S102: When the positioning selection mode is 1, it is a single-ended power supply, and the voltage U at one end is recorded. A 、U B 、U C , current I A , I B , I C Sampling value, single-ended power supply fault ranging and identification;

[0185] S103. Calculate the effective value of voltage and current and the real and imaginary parts of each data using the data.

[0186] As described in steps S101-S103 above, based on the fault location SCEFRFLO function module, when the input TRIGG_XCOF is TRUE, the voltage U at the M terminal is first recorded. A 、U B 、U C , current I A , I B , I C The sampling value and the number of waveforms recorded are not less than 8 cycles. The effective values ​​of voltage and current as well as the real and imaginary parts of each data are calculated using the data. After the series of data is calculated and processed, the fault type is determined. When the fault type is determined, single-ended power supply fault ranging or single-ended power supply fault ranging is performed, and the average value is calculated using the 8-cycle ranging number. The result is the fault location.

[0187] When the positioning selection mode = 1, it is a single-ended power supply, and only one-end voltage U is recorded. A 、U B 、U C , current I A , I B , I C Sampling value, only single-ended power supply fault ranging judgment is performed.

[0188] S2. Determine the fault type according to the fault recording data; wherein the fault types include single-phase grounding, three-phase short circuit, inter-phase grounding short circuit, and inter-phase non-grounding short circuit.

[0189] Step S2 specifically includes:

[0190] S201. Calculate the current and voltage of phase A, phase B, and phase C according to the fault recording data. The calculation formula is:

[0191] A phase current power frequency variation:

[0192] Phase B current power frequency variation:

[0193] Phase C current power frequency variation:

[0194] in, The A-phase current vector value of the k-sampling point in the current fault cycle;

[0195] Represents the A-phase current vector value at k sampling points one cycle before the fault;

[0196] Represents the A-phase current vector value at k sampling points 2 cycles before the fault;

[0197] The B-phase current vector value of the k-sampling point in the current fault cycle;

[0198] Represents the B-phase current vector value at k sampling points one cycle before the fault;

[0199] represents the B-phase current vector value at k sampling points 2 cycles before the fault;

[0200] Represents the C-phase current vector value at the k sampling point of the current fault cycle;

[0201] Represents the C-phase current vector value at k sampling points one cycle before the fault;

[0202] represents the C-phase current vector value at the k sampling point 2 cycles before the fault;

[0203] Calculate using the local measurement value:

[0204]

[0205] Current sequence component calculation:

[0206] Zero sequence:

[0207] Positive sequence:

[0208] Negative sequence:

[0209] Voltage sequence component calculation:

[0210] Zero sequence:

[0211] Positive sequence:

[0212] Negative sequence:

[0213] Superposition current:

[0214] Phase A current:

[0215] Phase B current:

[0216] Phase C current:

[0217] Superimposed voltage:

[0218] Phase A voltage:

[0219] Phase B voltage:

[0220] Phase C voltage:

[0221] The above operation factors,

[0222] S202: Determine the fault type based on the current and voltage of phase A, phase B, and phase C. The fault type determination method is:

[0223] When 0≤|I1-I2|≤0.2*I n And 0≤|I0-I1|≤0.2*I n and 0≤|I0-I2|≤0.2*In and and and and When the fault type is determined to be single-phase grounding of phase A;

[0224] When 0≤|I1-I2|≤0.2*I n And 0≤|I0-I1|≤0.2*I n N0≤|I0-I2|≤0.2*I n and and and and When the fault type is determined to be single-phase grounding of phase B;

[0225] When 0≤|I1-I2|≤0.2*I n And 0≤|I0-I1|≤0.2*I n and 0≤|I0-I2|≤0.2*I n and and and and When the fault type is determined to be single-phase grounding of phase C;

[0226] When 0≤|I1-I2|≤0.2*I n

[0227] and and and When the fault type is determined to be a short circuit between phases AB without grounding;

[0228] when and and and When , the fault type is determined to be BC phase-to-phase short circuit;

[0229] When 0≤|I1-I2|≤0.2*I n

[0230] and and and When , the fault type is determined to be CA phase-to-phase short circuit;

[0231] When 0.2*I n <|I1-I2|

[0232] and and and When , the fault type is determined to be a ground short circuit between phases AB;

[0233] When 0.2*I n <|I1-I2|

[0234] and and and When , the fault type is determined to be a ground short circuit between phases BC;

[0235] When 1.5*IN<|I1-I0| and 1.5*IN<|I1-I2|

[0236] and and and When , it is determined that the fault type is three-phase short circuit;

[0237] in:

[0238] I1 represents the effective amplitude of the positive sequence current in the current fault cycle;

[0239] I2 represents the effective amplitude of the negative sequence current in the current fault cycle;

[0240] I0 represents the effective amplitude of the zero-sequence current in the current fault cycle;

[0241] Indicates the AB phase fault component line current vector value of the current fault cycle;

[0242] Indicates the BC phase fault component line current vector value of the current fault cycle;

[0243] Represents the line current vector value of the CA phase fault component in the current fault cycle;

[0244] I n Indicates the secondary rated current value of the current transformer CT, generally 5A or 1A, depending on the actual setting.

[0245] S3. According to the fault type, a symmetrical fault analysis method is used to calculate the fault impedance.

[0246] Since the fault types are divided into single-phase grounding fault, inter-phase ungrounded fault, inter-phase grounding fault, and three-phase short circuit, and the fault type can be determined by the above criteria, the symmetrical fault analysis method can be used to calculate the fault impedance, that is, step S3 specifically includes:

[0247] S301, single-phase grounding fault:

[0248] Construct a single-phase ground fault network, such as Figure 2 As shown, the following equivalent formula can be obtained:

[0249]

[0250] Since it is single-phase grounding, there are: Taking negative sequence current as the standard, the simplified formula is:

[0251]

[0252] In order to realize fault location estimation, the imaginary part is taken to eliminate the influence of transition resistance and the fault impedance is calculated as:

[0253]

[0254] If the fault phase is determined, the phase voltage and negative sequence current of the corresponding phase can be input to obtain the fault impedance.

[0255] S302, constructing a phase-to-phase short circuit ungrounded fault network, such as Figure 3 As shown, the following equivalent formula can be obtained:

[0256]

[0257] Because there are: and Taking negative sequence current as the standard, the simplified formula is:

[0258]

[0259] In order to realize fault location estimation, the imaginary part is taken to eliminate the influence of transition resistance and the fault impedance is calculated as:

[0260]

[0261] If the two phases that are faulty are determined, the sequence voltage and sequence current of the corresponding phases can be input to obtain the fault impedance.

[0262] S303, constructing a phase-to-phase short-circuit grounding fault network, such as Figure 4 As shown, the following simplified equivalent formula can be obtained:

[0263]

[0264] In order to realize fault location estimation, the imaginary part is taken to eliminate the influence of transition resistance and the fault impedance is calculated as:

[0265]

[0266] If the two phases that are faulty are determined, the sequence voltage and sequence current of the corresponding phases can be input to obtain the fault impedance.

[0267] S304, constructing a phase-to-phase short-circuit grounding fault network, such as Figure 5 As shown, the following simplified equivalent formula can be obtained:

[0268]

[0269] In order to realize fault location estimation, the imaginary part is taken to eliminate the influence of transition resistance and the fault impedance is calculated as:

[0270]

[0271] When the fault type is determined, the sequence voltage and sequence current of the corresponding phase are input to obtain the fault impedance.

[0272] S4. Determine the number of lines, and set the positive sequence impedance value, negative sequence impedance value, zero sequence impedance value per unit length of each line segment, and the positive sequence impedance compensation value of the terminal of each line segment.

[0273] By setting the positive sequence impedance per unit length of each line n1 (n represents the segment number, n = 1, 2, 3 ..., 10) value, negative sequence impedance (= positive sequence impedance), zero sequence impedance χ n0 Value, positive sequence impedance compensation X of each section of the line terminal np value, the fault location can be calculated.

[0274] S5. Calculate an average value of the multiple fault impedances, and calculate the fault distance based on the average value, the negative sequence impedance value, the zero sequence impedance value, and the positive sequence impedance compensation value of the connection head of each section of the line to determine the fault location.

[0275] Use the formula in step S3 to calculate the average value of at least three data points to obtain X012 total_平均值 , X1 total_平均值 , and convert it into a primary value, specific conversion unit:

[0276]

[0277] Calculating the fault distance specifically includes:

[0278] S501. For a single-phase grounding fault, the distance determination method for each fault point on the entire line is as follows:

[0279] The entire line is determined to be divided into 10 sections, and the total plant of the entire line is calculated as:

[0280] 1) When X012 total_平均值_1 ≤2*(X 1p +X 1p +3*X 1p )+2*χ 11 *L1+χ 10 *L1, indicating that the fault is within line L1; the specific distance measurement is:

[0281] (meets the requirements), if L is calculated 故障位置>L1 indicates that the distance measurement exceeds the limit.

[0282] 2) When

[0283] 2*(X 1p +X 1p +3*X 1p )+2*χ 11 *L1+χ 10 *L1 <X012 total_平均值_1 ≤2*(X 1p +X 1p +3*X 1p )+2*χ 11 *L1+χ10*L1+2*(X 2p +X 2p +3*X 2p )+2*χ 21 *L2+χ 20 *L2, indicating that the fault is within line L2; the specific distance measurement is:

[0284] (meets the requirements), if L is calculated 故障位置 >L1+L2 indicates that the distance measurement exceeds the limit.

[0285] 3) When

[0286] 2*(X 1p +X 1p +3*X 1p )+2*χ 11 *L1+χ 10 *L1+2*(X 2p +X 2p +3*X 2p )+2*χ 21 *L2+χ 20 *L2 <X012 total_平均值_1 ≤2*(X 1p +X 1p +3*X 1p )+2*χ 11 *L1+χ 10 *L1+2*(X 2p +X 2p +3*X 2p )+2*χ 21 *L2+χ 20 *L2+2*(X 3p +X 3p +3*X 3p )+2*χ 31 *L3+χ 30 *L3, indicating that the fault is within line L3; the specific distance measurement is:

[0287]

[0288] (meets the requirements), if L is calculated 故障位置 >L1+L2+L3 indicates that the distance measurement exceeds the limit.

[0289] 4) When

[0290] 10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3 <X012 total_平均值_1 ≤10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4

[0291] When , it means the fault is in line L4; the specific distance measurement is:

[0292] (meets the requirements), if L is calculated 故障位置 >L1+L2+L3+L4 indicates that the ranging exceeds the limit.

[0293] 5) When

[0294] 10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4 <X012 total_平均值_1 ≤10*X 1p +2*χ11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4+10*X 5p +2*χ 51 *L5+χ 50 *L5

[0295] When , it means the fault is within line L5; the specific distance measurement is:

[0296] (meets the requirements), if L is calculated 故障位置 >L1+L2+L3+L4+L5 indicates that the ranging is out of limit.

[0297] 6) When

[0298] 10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4+10*X 5p +2*χ 51 *L5+χ 50 *L5 <X012 total_平均值_1 ≤10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4+10*X 5p +2*χ51 *L5+χ 50 *L5+10*X 6p +2*χ 61 *L6+χ 60 *L6

[0299] When , it means the fault is in line L6; the specific distance measurement is:

[0300] (meets the requirements), if L is calculated 故障位置 >L1+L2+L3+L4+L5+L6 indicates that the ranging exceeds the limit.

[0301] 7) When

[0302] 10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4+10*X 5p +2*χ 51 *L5+χ 50 *L5+10*X 6p +2*χ 61 *L6+χ 60 *L6 <X012 total_平均值_1 ≤10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4+10*X 5p +2*χ 51 *L5+χ 50 *L5+10*X 6p +2*χ 61 *L6+χ 60 *L6+10*X 7p +2*χ71 *L7+χ 70 *L7

[0303] When , it means the fault is in line L7; the specific distance measurement is:

[0304] (meets the requirements), if L is calculated 故障位置 >L1+L2+L3+L4+L5+L6+L7 indicates that the ranging exceeds the limit.

[0305] 8) When

[0306] 10*X 1p +2*χ 11 *L1+χ10*L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4+10*X 5p +2*χ 51 *L5+χ 50 *L5+10*X 6p +2*χ 61 *L6+χ 60 *L6+10*X 7p +2* χ7 1*L7+χ 70 *L7 <X012 total_平均值_1 ≤10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4+10*X 5p +2*χ 51 *L5+χ 50 *L5+10*X 6p +2*χ 61 *L6+χ 60 *L6+10*X 7p +2*χ71 *L7+χ 70 *L7+10*X 8p +2*χ 81 *L8+χ 80 *L8

[0307] When , it means the fault is in line L8; the specific distance measurement is:

[0308] (meets the requirements), if L is calculated 故障位置 >L1+L2+L3+L4+L5+L6+L7+L8 indicates that the ranging is out of limit.

[0309] 9) When

[0310] 10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4+10*X 5p +2*χ 51 *L5+χ 50 *L5+10*X 6p +2*χ 61 *L6+χ 60 *L6+10*X 7p +2*χ 71 *L7+χ 70 *L7+10*X 8p +2*χ 81 *L8+χ 80 *L8 <X012 total_平均值_1 ≤10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4+10*X 5p+2*χ 51 *L5+χ 50 *L5+10*X 6p +2*χ 61 *L6+χ 60 *L6+10*X 7p +2*χ 71 *L7+χ 70 *L7+10*X 8p +2*χ 81 *L8+χ 80 *L8+10*X 9p +2*χ 91 *L9+χ 90 *L9 indicates that the fault is within line L9; the specific distance measurement is:

[0311] (meets the requirements), if L is calculated 故障位置 >L1+L2+L3+L4+L5+L6+L7+L8+L9 indicates that the ranging is out of limit.

[0312] 10) When

[0313] 10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4+10*X 5p +2*χ 51 *L5+χ 50 *L5+10*X 6p +2*χ 61 *L6+χ 60 *L6+10*X 7p +2*χ 71 *L7+χ 70 *L7+10*X 8p +2*χ 81 *L8+χ 80 *L8+10*X 9p +2*χ 91 *L9+χ 90 *L9 <X012 total_平均值_1 ≤10*X 1p +2*χ11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4+10*X 5p +2*χ 51 *L5+χ 50 *L5+10*X 6p +2*χ 61 *L6+χ 60 *L6+10*X 7p +2*χ 71 *L7+χ 70 *L7+10*X 8p +2*χ 81 *L8+χ 80 *L8+10*X 9p +2*χ 91 *L9+χ 90 *L9+10*X 10p +2*χ 101 *L 10 +χ 100 *L 10

[0314] When , it means the fault is within line L10; the specific distance measurement is:

[0315] (meets the requirements), if L is calculated 故障位置 >L1+L2+L3+L4+L5+L6+L7+L8+L9+L 10 Indicates that the distance measurement exceeds the limit.

[0316] S502. For phase-to-phase grounding faults, phase-to-phase ungrounded faults, and three-phase short-circuit faults, the distance determination method for each fault point on the entire line is as follows:

[0317] 1) When X1 total_平均值_1 ≤2*X 1p +χ 11 *L1, indicating that the fault is within line L1; the specific distance measurement is:

[0318] (meets the requirements), if L is calculated 故障位置 >L1 indicates that the distance measurement exceeds the limit.

[0319] 2) When 2*X 1p +χ 11 *L 11 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2, indicating that the fault is within line L2; the specific distance measurement is:

[0320] (meets the requirements), if L is calculated 故障位置 >L1+L2 indicates that the distance measurement exceeds the limit.

[0321] 3) When

[0322] 2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3

[0323] When , it means the fault is in line L3; the specific distance measurement is:

[0324] (meets the requirements), if L is calculated 故障位置 >L1+L2+L3 indicates that the distance measurement exceeds the limit.

[0325] 4) When

[0326] 2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3 <X1 tota_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ31*L3+2*X 4p +χ 41 *L4

[0327] When , it means the fault is in line L4; the specific distance measurement is:

[0328]

[0329] (meets the requirements), if L is calculated 故障位置 >L1+L2+L3+L4 indicates that the ranging exceeds the limit.

[0330] 5) When

[0331] 2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ51*L5 indicates that the fault is within line L5; the specific distance measurement is:

[0332] (meets the requirements), if L is calculated 故障位置 >L1+L2+L3+L4+L5 indicates that the ranging is out of limit.

[0333] 6) When

[0334] 2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p+χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p +χ 61 *L6

[0335] When , it means the fault is in line L6; the specific distance measurement is:

[0336] (meets the requirements), if L is calculated 故障位置 >L1+L2+L3+L4+L5+L6 indicates that the ranging exceeds the limit.

[0337] 7) When

[0338] 2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p +χ 61 *L6 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p +χ 61 *L6+2*X 7p +χ 71 *L7 indicates that the fault is within line L7; the specific distance measurement is:

[0339] (meets the requirements), if L is calculated 故障位置 >L1+L2+L3+L4+L5+L6+L7 indicates that the ranging exceeds the limit.

[0340] 8) When

[0341] 2*X1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p +χ 61 *L6+2*X 7p +χ 71 *L7 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p +χ 61 *L6+2*X 7p +χ 71 *L7+2*X 8p +χ 81 *L8

[0342] When , it means the fault is in line L8; the specific distance measurement is:

[0343] (meets the requirements), if L is calculated 故障位置 >L1+L2+L3+L4+L5+L6+L7+L8 indicates that the ranging is out of limit.

[0344] 9) When

[0345] 2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p +χ 61 *L6+2*X7p +χ 71 *L7+2*X 8p +χ 81 *L8 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p +χ 61 *L6+2*X 7p +χ 71 *L7+2*X 8p +χ 81 *L8+2*X 9p +χ 91 *L9 indicates that the fault is within line L9; the specific distance measurement is:

[0346] (meets the requirements), if L is calculated 故障位置 >L1+L2+L3+L4+L5+L6+L7+L8+L9 indicates that the ranging is out of limit.

[0347] 10) When

[0348] 2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p +χ 61 *L6+2*X 7p +χ 71 *L7+2*X 8p +χ 81 *L8+2*X 9p +χ 91 *L9 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p +χ 61 *L6+2*X 7p +χ 71 *L7+2*X 8p +χ 81 *L8+2*X 9p +χ 91 *L9+2*X 10p +χ 101 *L 10 When , it means the fault is within line L10; the specific distance measurement is:

[0349] (meets the requirements), if L is calculated 故障位置 >L1+L2+L3+L4+L5+L6+L7+L8+L9+L 10 Indicates that the distance measurement exceeds the limit.

[0350] S6. Output the fault location, fault type, fault line segment interval, and whether the fault distance is within the entire line range.

[0351] The present invention uses fault recording data to identify the fault type, and then uses a symmetrical fault analysis method to calculate the fault impedance according to the fault type. The positive-sequence impedance value, negative-sequence impedance value, and zero-sequence impedance value per unit length of each line segment, as well as the positive-sequence impedance compensation value of the connection head of each line segment, are set. The fault distance is calculated in combination with the average value of multiple fault impedances to determine the fault location. The fault analysis impedance method is used to locate single-end power supply faults and double-end power supply faults, which can accurately locate the fault position, saving manpower and material resources. At the same time, the fault line segment interval and whether the fault distance is within the entire line range can be output, thereby improving positioning accuracy.

[0352] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the claims and their equivalents.

Claims

1. A fault location method for filtering out wire joint impedance, characterized in that: The method comprises: S1. Record the fault waveform data after the protection action; S2. Determine the fault type according to the fault recording data; wherein the fault types include single-phase grounding, three-phase short circuit, inter-phase grounding short circuit, and inter-phase non-grounding short circuit; S3. Calculate the fault impedance using a symmetrical fault analysis method according to the fault type. S4. Determine the number of lines, and set the positive sequence impedance value, negative sequence impedance value, zero sequence impedance value per unit length of each line segment, and the positive sequence impedance compensation value of the terminal of each line segment; S5. Calculate an average value of the plurality of fault impedances, and calculate the fault distance based on the average value, the negative-sequence impedance value, the zero-sequence impedance value, and the positive-sequence impedance compensation value of the connection head of each section of the line to determine the fault location; S6. Output the fault location, fault type, fault line segment interval, and whether the fault distance is within the entire line range.

2. A fault location method for filtering out wire joint impedance according to claim 1, characterized in that: Step S1 specifically includes: S101. When the input information TRIGG_XCOF is TRUE, determine the value of the positioning selection mode; S102: When the positioning selection mode is 1, it is a single-ended power supply, and the voltage U at one end is recorded. A 、U B 、U C , current I A , I B , I C Sampling value, single-ended power supply fault ranging and identification; S103. Calculate the effective value of voltage and current and the real and imaginary parts of each data using the data.

3. A fault location method for filtering out wire joint impedance according to claim 2, characterized in that: The step S2 specifically includes: S201, calculating the fault components of phase A, phase B, and phase C according to the fault recording data; S202: Determine the fault type based on the current and voltage of phase A, phase B, and phase C.

4. A fault location method for filtering out wire joint impedance according to claim 3, characterized in that: In step S201, the calculation formula is: A phase current power frequency variation: Phase B current power frequency variation: Phase C current power frequency variation: in, The A-phase current vector value of the k-sampling point in the current fault cycle; Represents the A-phase current vector value at k sampling points one cycle before the fault; Represents the A-phase current vector value at k sampling points 2 cycles before the fault; The B-phase current vector value of the k-sampling point in the current fault cycle; Represents the B-phase current vector value at k sampling points one cycle before the fault; represents the B-phase current vector value at k sampling points 2 cycles before the fault; Represents the C-phase current vector value at the k sampling point of the current fault cycle; Represents the C-phase current vector value at k sampling points one cycle before the fault; represents the C-phase current vector value at the k sampling point 2 cycles before the fault; Calculate using the local measurement value: Current sequence component calculation: Zero sequence: Positive sequence: Negative sequence: Voltage sequence component calculation: Zero sequence: Positive sequence: Negative sequence: Superposition current: Phase A current: Phase B current: Phase C current: Superimposed voltage: Phase A voltage: Phase B voltage: Phase C voltage:

5. A fault location method for filtering out wire joint impedance according to claim 4, characterized in that: In step S202, the fault type is determined as follows: When 0≤|I1-I2≤0.2*I n And 0≤|I0-I1|≤0.2*I n and 0≤|I0-I2|≤0.2*I n and and and and When the fault type is determined to be single-phase grounding of phase A; When 0≤|I1-I2|≤0.2*I n And 0≤|I0-I1|≤0.2*I n and 0≤|I0-I2|≤0.2*I n and and and and When the fault type is determined to be single-phase grounding of phase B; When 0≤|I1-I2|≤0.2*I n And 0≤|I0-I1|<0.2*I n and 0≤|I0-I2|≤0.2*I n and and and and When the fault type is determined to be single-phase grounding of phase C; When 0≤|I1-I2|≤0.2*I n and and and When the fault type is determined to be a short circuit between phases AB without grounding; when and and and When , the fault type is determined to be BC phase-to-phase short circuit; When 0≤|I1-I2|≤0.2*I n and and and When , the fault type is determined to be CA phase-to-phase short circuit; When 0.2*I n <|I1-I2| and and and When , the fault type is determined to be a ground short circuit between phases AB; When 0.2*I n <|I1-I2| and and and When , it is determined that the fault type is a ground short circuit between phases BC; When 1.5*IN<|I1-I0| and 1.5*IN<|I1-I2| and and and When , it is determined that the fault type is three-phase short circuit; Where I1 represents the effective amplitude of the positive sequence current in the current fault cycle; I2 represents the effective amplitude of the negative sequence current in the current fault cycle; I0 represents the effective amplitude of the zero-sequence current in the current fault cycle; Indicates the AB phase fault component line current vector value of the current fault cycle; Indicates the BC phase fault component line current vector value of the current fault cycle; Indicates the line current vector value of the CA phase fault component in the current fault cycle; I n Indicates the secondary rated current value of the current transformer CT.

6. A fault location method for filtering out wire joint impedance according to claim 5, characterized in that: The step S3 specifically includes: S301. Construct a single-phase ground fault network and derive the following equivalent equation: Since it is single-phase grounding, there are: Taking negative sequence current as the standard, the simplified formula is: By taking the imaginary part to eliminate the influence of transition resistance, the fault impedance is calculated as: When the fault type is determined, the phase voltage and negative sequence current of the corresponding phase are input to calculate the fault impedance; S302. Construct a phase-to-phase short-circuit ungrounded fault network and derive the following equivalent equation: Because there are: and Taking negative sequence current as the standard, the simplified formula is: By taking the imaginary part to eliminate the influence of transition resistance, the fault impedance is calculated as: When the fault type is determined, the sequence voltage and sequence current of the corresponding phase are brought in to obtain the fault impedance; S303. Construct a phase-to-phase short-circuit grounding fault network and derive the following simplified equivalent formula: By taking the imaginary part to eliminate the influence of transition resistance, the fault impedance is calculated as: When the fault type is determined, the sequence voltage and sequence current of the corresponding phase are brought in to obtain the fault impedance; S304. Construct a phase-to-phase short-circuit grounding fault network and derive the following simplified equivalent equation: By taking the imaginary part to eliminate the influence of transition resistance, the fault impedance is calculated as: When the fault type is determined, the sequence voltage and sequence current of the corresponding phase are input to obtain the fault impedance.

7. A fault location method for filtering out wire joint impedance according to claim 6, characterized in that: In the step S4, The positive sequence impedance value is denoted as χ n1 (n represents the segment number, n = 1, 2, 3…, 10); The negative sequence impedance value is equal to the positive sequence impedance value; The zero-sequence impedance value is recorded as X n0 ; The positive sequence impedance compensation value of each line terminal is recorded as X np .

8. A fault location method for filtering out wire joint impedance according to claim 7, characterized in that: In step S5, calculating the average value of the plurality of fault impedances specifically includes: At least three times of fault impedance data are used to calculate the average value X012 total_平均值 , Xl total_平均值 , and convert it into a primary value, specific conversion unit:

9. A fault location method for filtering out wire joint impedance according to claim 8, characterized in that: In step S5, calculating the fault distance specifically includes: S501. For a single-phase grounding fault, the distance determination method for each fault point on the entire line is as follows: 1) Determine the number of lines to be 10 sections; When X012 total_平均值_1 ≤2*(X 1p +X 1p +3*X 1p )+2*χ 11 *L1+χ 10 *L1, indicating that the fault is within line L1; the specific distance measurement is: Indicates that the requirements are met. If L is calculated 故障位置 >L1 means the distance measurement exceeds the limit; 2) When 2*(X 1p +X 1p +3*X 1p )+2*χ 11 *L1+χ 10 *L1<X012 total_平均值_1 ≤2*(X 1p +X 1p +3*X 1p )+2*χ 11 *L1+χ 10 *L1+2*(X 2p +X 2p +3*X 2p )+2*χ 21 *L2+χ 20 *L2, indicating that the fault is within line L2; the specific distance measurement is: ， Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2 means the distance measurement exceeds the limit; 3) When 2*(X 1p +X 1p +3*X 1p )+2*χ 11 *L1+χ 10 *L1+2*(X 2p +X 2p +3*X 2p )+2*χ 21 *L2+χ 20 *L2 <X012 total_平均值_1 ≤2*(X 1p +X 1p +3*X 1p )+2*χ 11 *L1+χ 10 *L1+2*(X 2p +X 2p +3*X 2p )+2*χ 21 *L2+χ 20 *L2+2*(X 3p +X 3p +3*X 3p )+2*χ 31 *L3+χ 30 *L3, indicating that the fault is within line L3; the specific distance measurement is: ， Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3 means the distance measurement exceeds the limit; 4) When 10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3 <X012 total_平均值_1 ≤10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4 indicates that the fault is within line L4; the specific distance measurement is: Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4 means the ranging is out of limit; 5) When 10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4 < X012 total_平均值_1 ≤10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4+10*X 5p +2*χ 51 *L5+χ 50 *L5, it indicates that the fault is within the line L5; the specific distance measurement is: Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4+L5 means the ranging is out of limit; 6) When 10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4+10*X 5p +2*χ 51 *L5+χ 50 *L5 < X012 total_平均值_1 ≤10*X 1p +2*χ[[ID=SS35]] 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4+10*X 5p +2*χ 51 *L5+χ 50 *L5+10*X ' 6p +2*χ 61 *L6+χ 60 *L6, it indicates that the fault is within line L6; the specific distance measurement is: Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4+L5+L6 means the ranging is out of limit; 7) When 10*X 1p +2*χ 11 *L1 + χ 10 *L1 + 10*X 2p +2*χ 21 *L2 + χ 20 *L2 + 10*X 3p +2*χ 31 *L3 + χ 30 *L3 + 10*X 4p +2*χ 41 *L4 + χ 40 *L4 + 10*X 5p +2*χ 51 *L5 + χ 50 *L5 + 10*X 6p +2*χ 61 *L6 + χ 60 *L6 < X012 total_平均值_1 ≤10*X 1p +2*χ 11 *L1 + χ 10 *L1 + 10*X 2p +2*χ 21 *L2 + χ 20 *L2 + 10*X 3p +2*χ 31 *L3 + χ 30 *L3 + 10*X 4p +2*χ 41 *L4 + χ 40 *L4 + 10*X[[ID=6​​​​​​​​​​​​​​​​​ Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4+L5+L6+L7 indicates that the ranging is out of limit; 8) When 10*X 1p +2*χ 11 *L1 + χ 10 *L1 + 10*X 2p +2*χ 21 *L2 + χ 20 *L2 + 10*X 3p +2*χ 31 *L3 + χ 30 *L3 + 10*X 4p +2*χ 41 *L4 + χ 40 *L4 + 10*X 5p +2*χ 51 *L5 + χ 50 *L5 + 10*X 6p +2*χ 61 *L6 + χ 60 *L6 + 10*X<000022​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​ Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4+L5+L6+L7+L8 indicates that the ranging is out of limit; 9) When 10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4+10*X 5p +2*χ 51 *L5+χ 50 *L5+10*X 6p +2*χ 61 *L6+χ 60 *L6+10*X 7p +2*x 71 *L7+x 70 *L7+10*X 8p +2*χ 81 *L8+χ 80 *L8<X012 total_平均值_1 ≤10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ<​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​ Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4+L5+L6+L7+L8+L9 indicates that the ranging is out of limit; 10) When 10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4+10*X 5p +2*χ 51 *L5+χ 50 *L5+10*X 6p +2*χ 61 *L6+χ 60 *L6+10*X 7p +2*χ 71 *L7+χ 70 *L7+10*X 8p +2*χ 81 *L8+χ 80 *L8+10*X 9p +2*χ 91 *L9+χ 90 *L9 < X012 total_平均值_1 ≤10*X 1p +2*χ 11 *L1+χ 10 *L1+10*X 2p +2*χ 21 *L2+χ 20 *L2+10*X 3p +2*χ 31 *L3+χ 30 *L3+10*X 4p +2*χ 41 *L4+χ 40 *L4+10*X 5p +2*χ 51 *L5+χ 50 *L5+10*X 6p +2*χ 61 *L6+χ 60 *L6+10*X 7p +2*χ 71 *L7+χ 70 *L7+10*X 8p +2*χ 81 *L8+χ 80 *L8+10*X 9p +2*χ 91 *L9+χ 90 *L9+10*X 10p +2*χ 101 *L 10 +χ 100 *L 10 When , it means the fault is within line L10; the specific distance measurement is: Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4+L5+L6+L7+L8+L9+L 10 Indicates that the distance measurement exceeds the limit; S502. For phase-to-phase grounding faults, phase-to-phase ungrounded faults, and three-phase short-circuit faults, the distance determination method for each fault point on the entire line is as follows: 1) When X1 total_平均值_1 ≤2*X 1p +χ 11 *L1, indicating that the fault is within line L1; the specific distance measurement is: Indicates that the requirements are met. If L is calculated 故障位置 >L1 means the distance measurement exceeds the limit; 2) When 2*X 1p +χ 11 *L 11 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2, indicating that the fault is within line L2; the specific distance measurement is: Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2 means the distance measurement exceeds the limit; 3) When 2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3, indicating that the fault is within line L3; the specific distance measurement is: Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3 means the distance measurement exceeds the limit; 4) When 2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4 indicates that the fault is within line L4; the specific distance measurement is: , indicating that the requirements are met, if L is calculated 故障位置 >L1+L2+L3+L4 means the ranging is out of limit; 5) When 2*X 1p +χ 11 *L1+2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5 indicates that the fault is within line L5; the specific distance measurement is: Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4+L5 means the ranging is out of limit; 6) When 2*X 1p +χ 11 *L1+2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p +χ 61 *L6, indicating that the fault is within line L6; the specific distance measurement is: Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4+L5+L6 means the ranging is out of limit; 7) When 2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p +χ 61 *L6 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p +χ 61 *L6+2*X 7p +χ 71 *L7 indicates that the fault is within line L7; the specific distance measurement is: Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4+L5+L6+L7 indicates that the ranging is out of limit; 8) When 2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p +χ 61 *L6+2*X 7p +χ 71 *L7 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p +χ 61 *L6+2*X 7p +χ 71 *L7+2*X 8p +χ 81 *L8, indicating that the fault is within line L8; the specific distance measurement is: Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4+L5+L6+L7+L8 indicates that the ranging is out of limit; 9) When 2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p +χ 61 *L6+2*X 7p +χ 71 *L7+2*X 8p +χ 81 *L8 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p +χ 61 *L6+2*X 7p +χ 71 *L7+2*X 8p +χ 81 *L8+2*X 9p +χ 91 *L9 indicates that the fault is within line L9; the specific distance measurement is: Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4+L5+L6+L7+L8+L9 indicates that the ranging is out of limit; 10) When 2*X 1p +χ 11 *L 11 +2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p +χ 61 *L6+2*X 7p +χ 71 *L7+2*X 8p +χ 81 *L8+2*X 9p +χ 91 *L9 <X1 total_平均值_1 ≤2*X 1p +χ 11 *L1+2*X 2p +χ 21 *L2+2*X 3p +χ 31 *L3+2*X 4p +χ 41 *L4+2*X 5p +χ 51 *L5+2*X 6p +χ 61 *L6+2*X 7p +χ 71 *L7+2*X 8p +χ 81 *L8+2*X 9p +χ 91 *L9+2*X 10p +χ 101 *L 10 When , it means the fault is within line L10; the specific distance measurement is: Indicates that the requirements are met. If L is calculated 故障位置 >L1+L2+L3+L4+L5+L6+L7+L8+L9+L 10 Indicates that the distance measurement exceeds the limit.

Images